Keywords : Bur
ESTIMATION OF EFFECTS OF VARIOUS ROTARY CUTTING BURS IN THE SHEAR BOND STRENGTH OF THREE DISSIMILAR FLOWABLE COMPOSITES USED IN VARIOUS PEDODONTIC PROCEDURES- A SCANNING ELECTRON MICROSCOPIC CUM IN VITRO STUDY
European Journal of Molecular & Clinical Medicine,
2020, Volume 7, Issue 5, Pages 26-34
Aim: There have been tremendous modifications in the composition as well as in properties of composite resins in the recent past. This study was performed to assess the effects of usage of different rotary cutting burs in the shear bond strength of three different flowable composites on tooth surface used in various pedodontic procedures. Surface changes were also evaluated using Scanning Electron Microscopic (SEM). Materials & Methods: This study was attempted on sixty freshly extracted permanent mandibular molars. Initially teeth were sectioned at coronal one third and polished with abrasive paper made up of silicon carbide. The samples were separated into 2 groups of 30 teeth each. In group I, teeth were prepared using fissure carbide bur and in group II with coarse taper round end diamond bur. Teeth after preparation were again segregated into 3 groups. In Group A, prepared teeth were applied with Vertise Flow which is a self adhering type of flowable composite resin. In group B, all prepared teeth were applied with Dyad flow (Kerr) SAFC. In Group C samples, Tetric N Bond which is a self‑etch adhesive was applied on the dentin surface. Teeth were then subjected to universal testing machine for evaluation of shear bond strength. Surface texture characteristics and changes were further explored by Scanning Electron Microscopy. Results: Data thus obtained were compiled for statistical analysis by latest SPSS software package. Shear bond strength (SBS) in group C was 22.4 MPa, in group B was 15.1 MPA and in group A was 12.8 MPa in group I. However when checked in group II, group C had SBS of 18.2 MPa, group B had 12.6 MPa and group A had 11.2 MPa. Therefore, author noticed non- significant difference (P = 0.71) in SBS values of flowable composite resin (self-adhering)Group A) for surfaces prepared with carbide (Group I) and diamond (Group II) burs. Conclusion: The shear bond strength (SBS) of Tetric-N Flow was reported to be higher when compared to other tested materials. Dentinal surface those prepared with carbide bur showed higher shear bond strength for Tetric N Flow and Dyad-flow. Clinical Significance: In the present in vitro study, the overall breaking shear bond strength (SBS) was reported higher in samples those prepared with carbide burs. Also, Tetric N Flow expressed highest values among the studied composites. These findings are very crucial and have a clinical applicability in selection of type of burs for critical and prone pedodontic circumstances.